Stimulate Here, Respond There - From 15 Milliseconds to Meaning

A sound occurs to our left.

Before we know what was said, our auditory system may already be working to determine where it came from.

Tiny differences in the arrival time and intensity of sound between the two ears begin to be processed by specialized brainstem circuits. On the scale of milliseconds — and, for some binaural operations, with sensitivity to submillisecond differences — the organism is already transforming a physical disturbance in the environment into biologically usable differences.

This leads us to a BrainLatam question:

how much of a word has already begun to modify the Body-Territory before we even know that we heard a word?

This question finds a provocative window in the study by Van Hoornweder and colleagues on the N15, published in 2026 in Imaging Neuroscience.

Fifteen milliseconds may already contain a trajectory

The authors applied transcranial magnetic stimulation over the motor cortex and investigated the N15, an evoked potential detectable approximately 15 milliseconds after the pulse.

The most interesting result was spatial.

The main estimated source of the N15 did not exactly coincide with the point of maximum electric field produced by TMS. It appeared displaced rostrally, and this relationship also depended on stimulation dose.

Therefore, even within such a brief temporal window:

site of perturbation ≠ necessarily site of measured response.

Propagation may already exist between the two.

The N15 studied by Van Hoornweder is not an auditory potential, and we cannot claim that it detects phonemes. But the study offers another possibility for interpretation:

15 milliseconds are not necessarily too early for what entered the system to have already begun a journey.

Before “what?”, there may already be “where?”

The auditory system offers an especially interesting comparison.

To localize sounds in the horizontal plane, the brain uses differences between what reaches the two ears.

The medial superior olive (MSO) is especially involved in processing interaural time differences, while the lateral superior olive (LSO) makes strong use of interaural level differences. Circuits in the cochlear nucleus, superior olivary complex, and medial nucleus of the trapezoid body show cellular and synaptic specializations capable of preserving extraordinary temporal precision.

We do not yet need to know:

“someone is saying my name.”

The organism may already be representing differences related to:

time → intensity → frequency → location.

Therefore:

before recognizing what was said, the Body may already be calculating where it came from.

This is important for our 5D Consciousness proposal because it reinforces that something does not need to occupy attentional focus or receive a name in order to begin participating in the configuration of the Body-Territory.

From sound to phoneme

Now imagine someone pronouncing /ba/.

The phoneme does not arrive in the nervous system as a ready-made abstract unit.

It arrives as an acoustic wave.

In a classic study of auditory brainstem responses to speech, Akhoun and colleagues found an onset response approximately 6 ms after the stimulus and a frequency-following response that tracked temporal characteristics of /ba/ with an approximate delay of 14.6 ms.

This does not mean that the brain had “recognized /ba/” within 14.6 milliseconds.

It means something perhaps more interesting for our hypothesis:

physical differences that may later contribute to recognizing /ba/ are already being temporally represented very early.

Cortical discrimination of auditory regularities emerges later. The Mismatch Negativity — MMN — associated with automatic detection of auditory deviations typically appears approximately between 100 and 250 ms, depending on the paradigm and the feature being changed.

We may therefore imagine a trajectory:

sound → difference → transduction → localization → temporal representation → possible phonemic difference → possible word → meaning.

We do not need to find a magical instant in which sound “becomes” a phoneme.

There may instead be successive transformations.

The phoneme arrives situated

There is an important consequence.

The phoneme does not arrive merely as a phoneme.

It arrives:

from somewhere,

at a particular moment,

with a particular intensity,

in a particular voice,

within a sequence,

to a Body that already has a history.

Thus, the same /a/ pronounced behind me and in front of me may still belong to the same phonological category while encountering different spatial configurations of the Body-Territory.

That spatiality may recruit movement before lexical meaning is even available:

turning the head,

moving the eyes,

orienting attention,

preparing,

approaching,

withdrawing.

The territory is already participating before the word is ready.

Dehaene: when culture changes what sound can recruit

Stanislas Dehaene and colleagues show that learning to read reorganizes preexisting neural systems. Literacy changes visual processing, strengthens functional and anatomical relationships between graphemic and phonemic representations, and alters aspects of phonological coding itself.

This offers a fundamental bridge.

The brain did not evolve a region specifically dedicated to recognizing modern written letters. Learning reuses and reorganizes available circuits — what Dehaene calls neuronal recycling.

After literacy, hearing a phoneme may encounter a different Body-Territory.

The sound may recruit:

phoneme → articulatory movement → grapheme → word → memory → meaning.

Culture has become part of the possibilities available to that stimulus.

The previous encounter transformed the one who will encounter the next event.

Evaluate, Plan, and Do

Here we can explicitly introduce our BrainLatam hypothesis.

We propose three continuously available functional dimensions:

Evaluate → Plan → Do.

We are not proposing three fixed anatomical areas, nor are we claiming that neuroscience has demonstrated this division.

We are proposing three possible functions of the organism.

Evaluate: what difference appeared? Where did it come from? Is it familiar? Did something change?

Plan: what movements, predictions, or responses are possible?

Do: what action can be actualized?

Our later analogy with Judiciary, Legislature, and Executive — and with Politics, Religion, and Science — belongs to the BrainLatam conceptual model, not to the neurophysiological papers used here.

Attentional focus may increase the relative weight of one of these dimensions without requiring the others to stop participating.

A BrainLatam hypothesis for the first milliseconds

We can therefore formulate the hypothesis more precisely:

BrainLatam hypothesis: during the first 10–20 ms of an acoustic stimulus, differences that may later participate in a phonemic category may already be modifying the Body-Territory through the transduction and propagation of temporal, spectral, intensity, and spatial information.

This does not mean that there is an “N15 of the phoneme.”

It means that the phoneme recognized later may depend on a movement that began before the phoneme existed as an available category for the subject.

The TMS N15 offers us an analogy of rapid propagation.

Auditory physiology shows that information about sound is already being encoded on similar timescales.

Dehaene shows how learning and culture reorganize what those differences may later recruit.

And 5D Consciousness adds:

a difference does not need to be in attentional focus in order to already participate materially in the configuration that perceives Being.

From difference to meaning

Perhaps the most interesting sequence is not:

sound → phoneme → meaning.

We can open it further:

physical difference → transduction → localization → propagation → phonemic possibility → recognition → possible grapheme → word → meaning → new configuration of the Body-Territory.

And the final movement returns to the first.

Because after that word acquires meaning, the Body that encounters the next sound no longer needs to be exactly the same.

We may therefore say:

before we know what was said, the Body may already know where something came from. Before recognizing the phoneme, differences have already begun to modify the system. And before meaning appears, the encounter capable of producing it has already begun.

The first milliseconds do not need to contain the finished phoneme.

They may contain what will make it possible.

And perhaps this offers another way to understand 5D Consciousness:

meaning arrives after difference — but difference never needed to wait for meaning in order to begin moving the Body-Territory.

References

Van Hoornweder, S., Beck, M. M., Nielsen, J. D., Tomasevic, L., Meesen, R. L. J., Siebner, H. R., & Thielscher, A. (2026). Sources of the N15 TMS-evoked potential following motor cortex stimulation localize rostrals to TMS-induced electric fields and depend on dose. Imaging Neuroscience, 4. https://doi.org/10.1162/IMAG.a.1356
Shows that within approximately 15 ms, the detected response may already appear spatially displaced from the maximum perturbation, opening the possibility of thinking in terms of input → propagation → response, rather than localization alone.

Kandler, K., et al. (2025). Cellular and synaptic specializations for sub-millisecond precision in the mammalian auditory brainstem. Frontiers in Cellular Neuroscience.
Describes cellular and synaptic specializations in the auditory system capable of preserving extreme temporal precision, fundamental for binaural computations involved in sound localization.

Akhoun, I., Moulin, A., Jeanvoine, A., Ménard, M., Buret, F., Vollaire, C., Scorretti, R., Veuillet, E., Berger-Vachon, C., & Collet, L. (2008). The temporal relationship between speech auditory brainstem responses and the acoustic pattern of the phoneme /ba/ in normal-hearing adults. Clinical Neurophysiology, 119, 922–933. https://doi.org/10.1016/j.clinph.2007.12.010
Shows that temporal properties of a speech stimulus can already be represented measurably in the brainstem within a few milliseconds, without implying that the conscious phoneme or its meaning is already available.

Dehaene, S., Cohen, L., Morais, J., & Kolinsky, R. (2015). Illiterate to literate: behavioural and cerebral changes induced by reading acquisition. Nature Reviews Neuroscience, 16, 234–244. https://doi.org/10.1038/nrn3924
Shows how learning to read reorganizes preexisting circuits and strengthens grapheme–phoneme relationships, opening the possibility of understanding how culture and learning modify what a stimulus can recruit.

Dehaene, S., et al. (2010–2016). Work on neuronal recycling, literacy, and the organization of reading circuits.
Supports the idea that recent cultural capacities such as reading do not require evolutionarily new circuits built from scratch, but instead reuse and reorganize preexisting neural architectures.

Garrido, M. I., Kilner, J. M., Stephan, K. E., & Friston, K. J. (2009). The mismatch negativity: A review of underlying mechanisms. Clinical Neurophysiology, 120, 453–463.
Places MMN approximately within the 100–250 ms range and helps distinguish extremely early auditory encoding from later cortical processes related to the detection of regularities and differences.